GB895155A - Machine for making bolts, screws and similar headed metal fasteners - Google Patents

Abstract

895,155. Making bolts and screws; forging; rolling screw threads; slotting screw heads. NATIONAL MACHINERY CO. Oct. 19, 1959 [Oct. 30, 1958], No. 35375/59. Classes 83 (2), 83 (3) and 83 (4). A machine for making bolts, screws and the like comprises a header slide 602, Fig. 32, reciprocable on a bed frame 5 by a main crank-shaft 600 and adapted to perform two successive heading strokes upon a blank held in a single die 612 provided with an ejector 626, a roll threader 513, 514, Fig. 28, mounted on the bed frame and driven from the crank-shaft, and means for transferring to the roll threader headed blanks ejected from the die 612. The headed blanks 21, Fig. 6, are first pointed by pressing between dies 250, 251, a driver slot is then cut in the head by a saw 350, Fig. 7, the head is de-burred by a tool 407, Fig. 15b, and finally the thread is rolled. In another embodiment, Figs. 40, 41 (not shown) the blanks are transferred directly from the pointing to the thread rolling stations and are not slotted. Heading.-Rod or wire stock 7, Fig. 32, is fed by rolls through a die breast 603 at station C to abut against a stop 7a. Here it is severed by a shear 630, Fig. 35, pivoted on the die breast by a pin 632 and actuated by a cam 633 on side shaft 607 driven at half the crank-shaft speed through bevel gearing 606, 607, shaft 604, and spur gearing 508, 605, Fig. 33 (not shown). The shear transfers the cut blank to station D where it is pushed by an ejector 625 into transfer fingers 639, 640 which move it to station E opposite the die 612. The fingers are mounted on a member 631 also pivoted on pin 632 and driven by a cam 634 on the shaft 607. The shear 630 is biased by spring 637 and the transfer member 631 by spring 641. The header slide 602, Fig. 32, carries a pair of heading tools 613, 614 which act successively on the blank, Figs. 4, 5 (not shown). These tools are mounted on a holder 615 secured to a shaft 616 oscillated through linkage 619 by a cam 621 on shaft 607. An ejector 626 removes the headed blank from die 612. Both ejectors 625, 626 are actuated through linkage by a common cam 622, Fig. 33 (not shown), on shaft 611. Blanks transferring.-The ejected blanks fall down a shoot 8, Fig. 1, to an elevator 100 having a chain conveyer 110 which raises the blanks 20 to a pocket 115, Fig. 13, from which they fall on inclined rails 132 and are conveyed upwardly by teeth 140 on a chain conveyer 136. Incorrectly oriented blanks are either correctly positioned or are rejected by coil springs 146 depending from a plate 145. The rejected blanks fall to the bottom of elevator 100 which raises them again to pocket 115. Correctly positioned blanks pass along rails 141, 142, Fig. 15, to a pointing mechanism 201. Pointing.-A pointer feed and gating device 202 comprising a pair of parallel blades 220, 221, Figs. 17, 18 (not shown), delivers the blanks one at a time into notches 203-206 in a revolving dial 201. Adjacent each notch is a punch 266 and a die 250, Fig. 20, which rotate with the dial. Each die 250 is mounted in a block 254 for vertical movement and is raised to chamfer the end of the blank by a roller follower 257 running along a stationary cam track 259. Simultaneously the blank is supported from above by a hold-down assembly 261 having a roller follower 265 running along a stationary cam track 262. The die 250 is lowered positively by a pin 268 co-operating with a further stationary cam track 269. The blanks are removed from the notches in dial 201 by a member 279, and transferred by an adjacent dial 208 to a slotting dial 301, having eight notches 305. Slotting.-Each blank 21 is locked in its notch during slotting of the head by a jaw 354a, Fig. 24, on an arm 354 pivoted to the dial at 355 and actuated by a roller follower 359 co-operating with a stationary cam track 361. Adjacent each notch is a saw 338, Fig. 22, rotatably supported on a bracket 345 mounted for pivotal movement about an axis 316. All the saws are driven from a common motor 311, Fig. 21 (not shown), through spur and bevel gearing. The saws are normally biased upwards by spring units 343 but are moved downwardly about their pivots 316 to cut the slots, by plungers 347 carrying roller followers 349 co-operating with a stationary cam 340. De-burring.-The slotted blanks are removed to a de-burring dial 401, Fig. 15, having deburring stations 403-406 each provided with a cutter 407, Fig. 15b. As the dial rotates the blanks engage a stationary knurled member 410 causing them to rotate against the cutters 407 which trim off the burrs. Thread rolling.-From dial 401 the blanks 23 pass along rails 501, 502 to the roll threader, Fig. 28, comprising a stationary thread-rolling platen 514 and a reciprocating platen 513 mounted on a slide 511 driven by linkage 503, 507, Fig. 27 (not shown) from the shaft 604, Fig. 32. A reciprocating member 535 feeds the blanks between the roll platens and another reciprocating member 536 acts as a gate for the end of the rails 501, 502.